Arris SB8200 not reaching my Xfinity Plan speeds

I just upgraded to the Xfinity Gigabit Internet. I have a Arris SB8200 cable modem and tested the connection through ethernet port in the cable modem and my connection is maxing out at 375 Mbps on speed test. I have talked with Xfinity customer service twice and they say everything is fine, but on my end im not seeing the speeds I should be getting. Just a FYI, I also use to have the X1 modem on the 600Mbps plan but wasnt able to get those numbers either.

Event Log

05/28/2020 10:01	84000500	3	"SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=c8:63:fc:9f:33:69;CMTS-MAC=00:01:5c:64:cc:66;CM-QOS=1.1;CM-VER=3.1;"
05/28/2020 10:01	67061600	6	"DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.;CM-MAC=c8:63:fc:9f:33:69;CMTS-MAC=00:01:5c:64:cc:66;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:01	2436694066	6	"Honoring MDD; IP provisioning mode = IPv6"
01/01/1970 00:01	82000200	3	"No Ranging Response received - T3 time-out;CM-MAC=c8:63:fc:9f:33:69;CMTS-MAC=00:01:5c:64:cc:66;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:01	84000100	3	"SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=c8:63:fc:9f:33:69;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:01	84020200	5	"Lost MDD Timeout;CM-MAC=c8:63:fc:9f:33:69;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:01	84000100	3	"SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=c8:63:fc:9f:33:69;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:01	84020200	5	"Lost MDD Timeout;CM-MAC=c8:63:fc:9f:33:69;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"
01/01/1970 00:00	84000100	3	"SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=c8:63:fc:9f:33:69;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;"

Downstream Bonded Channels

Channel ID	Lock Status	Modulation	Frequency	Power	SNR/MER	Corrected	Uncorrectables
8	Locked	QAM256	405000000 Hz	-0.4 dBmV	39.4 dB	0	0
9	Locked	QAM256	411000000 Hz	-0.2 dBmV	39.4 dB	0	0
10	Locked	QAM256	417000000 Hz	-0.2 dBmV	39.3 dB	0	0
11	Locked	QAM256	423000000 Hz	-0.3 dBmV	38.9 dB	0	0
12	Locked	QAM256	429000000 Hz	-0.2 dBmV	38.5 dB	0	0
13	Locked	QAM256	435000000 Hz	-0.4 dBmV	37.9 dB	0	0
14	Locked	QAM256	441000000 Hz	-0.7 dBmV	37.7 dB	0	0
15	Locked	QAM256	447000000 Hz	-0.8 dBmV	38.1 dB	0	0
16	Locked	QAM256	453000000 Hz	-1.0 dBmV	37.4 dB	0	0
17	Locked	QAM256	459000000 Hz	-0.9 dBmV	37.9 dB	0	0
18	Locked	QAM256	465000000 Hz	-0.8 dBmV	39.1 dB	0	0
19	Locked	QAM256	471000000 Hz	-0.6 dBmV	39.3 dB	0	0
20	Locked	QAM256	477000000 Hz	-0.3 dBmV	39.4 dB	0	0
21	Locked	QAM256	483000000 Hz	-0.2 dBmV	39.5 dB	0	0
22	Locked	QAM256	489000000 Hz	-0.3 dBmV	39.3 dB	0	0
23	Locked	QAM256	495000000 Hz	-0.2 dBmV	39.4 dB	0	0
24	Locked	QAM256	501000000 Hz	-0.3 dBmV	39.3 dB	0	0
25	Locked	QAM256	507000000 Hz	-0.2 dBmV	39.5 dB	0	0
26	Locked	QAM256	513000000 Hz	-0.3 dBmV	39.1 dB	0	0
27	Locked	QAM256	519000000 Hz	-0.2 dBmV	39.0 dB	0	0
28	Locked	QAM256	525000000 Hz	-0.2 dBmV	38.7 dB	0	0
29	Locked	QAM256	531000000 Hz	-0.2 dBmV	38.8 dB	0	0
30	Locked	QAM256	537000000 Hz	-0.3 dBmV	38.9 dB	0	0
31	Locked	QAM256	543000000 Hz	-0.3 dBmV	39.0 dB	0	0
32	Locked	QAM256	549000000 Hz	-0.5 dBmV	39.2 dB	0	0
33	Locked	QAM256	555000000 Hz	-0.3 dBmV	39.2 dB	0	0
34	Locked	QAM256	561000000 Hz	-0.2 dBmV	39.3 dB	0	0
35	Locked	QAM256	567000000 Hz	-0.2 dBmV	39.3 dB	0	0
36	Locked	QAM256	573000000 Hz	-0.2 dBmV	39.2 dB	0	0
37	Locked	QAM256	579000000 Hz	-0.4 dBmV	39.3 dB	0	0
38	Locked	QAM256	585000000 Hz	-0.6 dBmV	39.2 dB	0	0
48	Locked	Other	685000000 Hz	-2.9 dBmV	36.8 dB	559970269	0

Upstream Bonded Channels

Channel	Channel ID	Lock Status	US Channel Type	Frequency	Width	Power
1	36	Locked	SC-QAM Upstream	36700000 Hz	6400000 Hz	49.0 dBmV
2	33	Locked	SC-QAM Upstream	17300000 Hz	6400000 Hz	46.0 dBmV
3	34	Locked	SC-QAM Upstream	23700000 Hz	6400000 Hz	48.0 dBmV
4	35	Locked	SC-QAM Upstream	30300000 Hz	6400000 Hz	49.0 dBmV

I would appreciate any assistance in resolving this issue. Thank You!

This conversation is no longer open for comments or replies and is no longer visible to community members.

Responses

mrbq1108

New Poster

•

15 Messages

5 years ago

Download the Ookla desktop app. You cannot really pull more than 400mbs via Firefox.

0

EG

Expert

•

111.4K Messages

5 years ago

FWIW, this may not be the direct cause of your issue, but it should be addressed regardless as it may be another problem just waiting to happen.

The upstream power is on the high side and it may be intermittently fluctuating even higher to out of spec levels. That can cause random disconnects, spontaneous re-booting of the modem, speed, packet loss, and latency problems.

In a self troubleshooting effort to try to obtain better connectivity / more wiggle room, check to see if there are there any excess/unneeded coax cable splitters in the line leading to the modem that can be eliminated/re-configured. Any splitters that remain should be high quality and cable rated for 5-1002 MHz, bi-directional, and no gold colored garbage types like GE, RadioShack, RCA, Philips, Leviton, Magnavox, and Rocketfish from big box stores like Home Depot, Lowes, Target, Wal-Mart etc. Splitters should be swapped with known to be good / new ones to test

If there aren't any unneeded splitters that can be eliminated and if your coax wiring setup can't be reconfigured so that there is a single two way splitter connected directly off of the drop from the street/pole with one port feeding the modem and the other port feeding the rest of the house/equipment with additional splits as needed, and you've checked all the wiring and fittings for integrity and tightness and refresh them by taking them apart then check for and clean off any corrosion / oxidation on the center wire and put them back together again, then perhaps it's best to book a tech visit to investigate and correct.

0

Your Home Network

Mediaman24

Arris SB8200 not reaching my Xfinity Plan speeds

mrbq1108

EG

New to the Community?